In the game of golf, a variety of clubs are used with varying loft angles (usually in 4 degree increments) which, when impacting the ball, impart more or less height and distance on the ball. Clubs called "drivers" have a slight angle away from vertical and are used to drive the ball a great distance horizontally with a relatively flat trajectory. As the player successfully advances the ball toward the green, less distance is required and he may select from a number of "irons" which have varying loft angles away from vertical. The shorter the required distance, the greater the angle required. Upon reaching the green, the ball is more gently hit with a "putter" so that it rolls along the grass which requires virtually no loft angle. Most golfers use up to 14 clubs with varying lofts at approximately four degree increments to play the game.
The need for multiple clubs creates a number of disadvantages such as significant cost to purchase a complete or partial set, a bag to contain said clubs, and a pull cart, a motorized riding cart, or caddy to transport the bag of clubs during the game.